The present invention relates to systems and methods for removing thrombus (clot) or emboli from a blood vessel. Devices and techniques currently employ various types of catheters that mechanically remove the clot, or drugs (lytic agents) that lyse (“dissolve”) the thrombus. U.S. Pat. No. 3,435,826 to Fogarty describes a balloon thrombectomy catheter that is introduced through a surgical incision in a blood vessel. The catheter is advanced such that the balloon is positioned distal to the thrombus, the balloon is inflated, and the catheter is retracted, pulling the thrombus to the surgical incision point where it is extracted by the surgeon. Other embolectomy catheters having an inflatable balloon at the distal end are described in U.S. Pat. Nos. 3,435,826; 4,561,439; 4,734,093; and 4,762,130. Embolectomy catheters having wire coils, corkscrews or meshes at their distal ends are described in U.S. Pat. Nos. 4,030,503, 4,706,671, 4,650,466, 8,366,663 and 8,758,364. Disadvantages of such mechanical thrombectomy means are that multiple passes are often required to completely remove the clot, and particles may embolize distally. U.S. Pat. Nos. 4,631,052, 4,664,112, 4,728,319, 5,001,488, and 5,092,839 describe various means to cut thrombus and/or capture debris. However, all pose a risk of injury to the vessel wall in use. A class of drugs (thrombolytics) is known in the art that act to dissolve the clot or thrombus. These drugs are commonly administered systemically by an intravenous route or locally through a variety of catheters known in the art. Systemic administration carries a risk of bleeding at remote locations in the body, including the brain, Localized delivery with catheters such as disclosed in U.S. Pat. Nos. 4,636,195, 4,610,662, and 4,573,966, may result in incomplete removal of the thrombus and/or distal embolization of thrombotic debris.
There is thus a need for, and it would be highly advantageous to have, a system and method for treating a vessel that contains thrombus.